title: JAK/STAT signaling and human in vitro myogenesis.
abstract: BACKGROUND
  A population of satellite cells exists in skeletal muscle. These cells are thought to be primarily responsible for postnatal muscle growth and injury-induced muscle regeneration. The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling cascade has a crucial role in regulating myogenesis. In rodent skeletal muscle, STAT3 is essential for satellite cell migration and myogenic differentiation, regulating the expression of myogenic factors. The aim of the present study was to investigate and compare the expression profile of JAK/STAT family members, using cultured primary human skeletal muscle cells.
  
  
  RESULTS
  Near confluent proliferating myoblasts were induced to differentiate for 1, 5 or 10 days. During these developmental stages, members of the JAK/STAT family were examined, along with factors known to regulate myogenesis. We demonstrate the phosphorylation of JAK1 and STAT1 only during myoblast proliferation, while JAK2 and STAT3 phosphorylation increases during differentiation. These increases were correlated with the upregulation of genes associated with muscle maturation and hypertrophy.
  
  
  CONCLUSIONS
  Taken together, these results provide insight into JAK/STAT signaling in human skeletal muscle development, and confirm recent observations in rodents.
authors.affiliation: Molecular Nutrition Unit, Deakin University, Burwood, Victoria, Australia. maritren@deakin.edu.au
authors.forename: Marissa K
authors.initials: MK
authors.lastname: Trenerry
authors.forename: Paul A
authors.initials: PA
authors.lastname: Della Gatta
authors.forename: David
authors.initials: D
authors.lastname: Cameron-Smith
mesh_terms: D002454:Cell Differentiation / Q000235:genetics; D002478:Cells, Cultured; D006801:Humans; D053613:Janus Kinase 1 / Q000235:genetics / Q000378:metabolism*; D053614:Janus Kinase 2 / Q000235:genetics / Q000378:metabolism*; D008297:Male; D024510:Muscle Development / Q000235:genetics / Q000502:physiology*; D018482:Muscle, Skeletal / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D050794:STAT1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D050796:STAT3 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D032496:Satellite Cells, Skeletal Muscle / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D015854:Up-Regulation
chemical_list: D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; C507904:JAK1 protein, human; C507924:JAK2 protein, human; D053613:Janus Kinase 1; D053614:Janus Kinase 2